Due to energy conservation awareness of the public and the building industry, new standards for energy efficient buildings include more stringent requirements on air tightness, insulation, mechanical ventilation, air cleaning and space heating - cooling loads.
As the loads for heating - cooling of the more energy efficient housing has been reduced, their air tightness brought up a need for a continuous mechanical exchange of indoor air with outdoor air to avoid potential health hazards and or house demage problems. Consequently, mechanical ventilation of new houses has become one of the required standard air conditioning services.
The required ventilation of new houses is being provided by various heat recovery ventilation systems build around various types of air to air heat exchangers equipped with defrost controls and with various effectiveness ratings. At below freezing temperatures these systems suffer ice build up problems causing up to 50% drop in heat recovery effectiveness and air delivery capacities.
The other space heating, cooling, humidifying, dehumidifying and air filtration services are being provided by various individual appliances and at considerable capital and operating costs.
The space heating services may be provided by appliances that may include a conventional warm air central heating, hydronic or a water circulating central heating system or an electric or fossil fuel fired unitary systems. For the central systems energy sources may be any fossil fuel or electric power, and the central furnaces and boilers may be conventional, high efficiency or ultra high efficiency condensing types.
The cooling systems may include indirect, direct or a combination of indirect - direct evaporative cooling systems, absorption chillers and mechanical vapour compression systems with the absorption and mechanical vapour compression systems providing simultaneously the required dehumidification and with the evaporative cooling systems providing the required humidification.
An independent dehumidification can be also provided by various mechanical vapour compression dehumidifiers and or dessicant dehumidifiers, and humidification by various concepts humidifiers.
Air filtration can be provided by various mechanical, chemical or electronic air filters, either built into the central heating cooling systems or by various unitary systems.
Integrated appliances providing the required heating - cooling humidification - dehumidification and air filtration are also available and usually combine the various individual appliances into a compact system with the heat recovery ventilation system as a separate system.
Because of the complexity and high capital and operating costs of the current art systems providing the above services for individual homes, a more simple and more energy efficient concept and apparatus capable of providing the described services is needed.